Observations on the feeding behavior of Parasitus coleoptratorum (L.) and Glyptholaspis americana (Berl.) revealed that the tritosternum functions in concert with the capitular groove of the gnathosoma as a fluid transport and grooming mechanism. Excess prey fluids overflowing into the postcapitular channel are redirected to the prebuccal region between the tritosternal laciniae and the capitular groove, preventing loss of food material.Surgical removal of the tritosternum results in an overflow of fluids from the region behind the tritosternal remnant onto the sternal area. Feeding efficiency studies on normal and tritosternectomized P. coleoptratorum showed that mites which lack a tritosternum feed on significantly more prey than do normal individuals. It is postulated that this increase reflects impairment of feeding efficiency and resultant food loss during each feeding episode.Grooming of the capitular groove is accomplished through the combined raking action of the lacinial pili and the deutosternal denticles. Substantial accumulations of debris were observed only in the capitular grooves of tritosternectomized mites.

Two experiments were conducted to examine the influence of foliar nitrogen, terpenes, and phenolics of Douglas-fir on the development of gypsy moth larvae. In the first experiment, foliar concentrations of nitrogen and allelochemicals were manipulated by fertilizing 3-year-old potted seedlings with 0 or 200 ppm nitrogen. Concentrations of foliar nitrogen (0.33-2.38%) were negatively correlated with the phenolics (15.8-24.4 mg/g). Sixth-instar larvae previously reared on current-year Douglas-fir needles were allowed to feed on these seedlings. Pupal weights (312.8-995.6 mg) were positively correlated with levels of foliar nitrogen, negatively correlated with amounts of foliar phenolics, and uncorrelated with terpene concentrations. In the second experiment, terpene and phenolic extracts from Douglas-fir foliage were incorporated at natural levels into artificial diets with high and low levels of protein nitrogen. Neonate larvae grew faster and were larger on the high nitrogen control diet (4.1-4.5%), however, fourth instars performed better on the control diet with low nitrogen levels (2.5-2.7%). Foliar terpenes incorporated into diet had little effect on neonate fitness, but may induce subtle physiological changes in later instar larvae. Phenolics, alone or in combination with terpenes, excessively suppressed growth and survival, with no individuals living through the fourth instar, regardless of the nitrogen level. Incorporating foliar phenolic extracts into artificial diet caused unnatural levels of toxicity and failed to clarify the effects of Douglas-fir phenolics on gypsy moth fitness. Foliar nitrogen is a key factor influencing gypsy moth development on Douglas fir, but may be mitigated to some degree by phenolics.

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Influence of dip, low, medium, and high vacuum applications of 5 inorganic chemicals on "Golden Delicious" apple was studied after 5 months of 0° C storage. Urea delayed ground color development, increased internal breakdown, but decreased firmness. Magnesium chloride induced severe incidence of a bitter pit-like symptom which did not have corky tissue. Soluble solids and titratable acidity were not